1. Field of the Invention
The present invention relates to a label printer having a label peeling mechanism for peeling printed labels from the web liner.
2. Description of the Related Art
Label printers for printing and peeling labels from the web liner on which the labels are carried are known from the literature. The label printer taught in Japanese Unexamined Patent Appl. Pub. H08-295323 (corresponding to U.S. Pat. No. 5,980,138), for example, conveys label paper having adhesive labels of a known constant length affixed to a web past a printing unit whereby the labels are printed. This label printer then conveys the printed label paper at an acute angle though a label peeling unit to sequentially peel the labels one by one from the web and dispense the printed peeled labels from a dispenser opening while detecting the labels with a peeled label detector.
This mode of printing and peeling the labels one by one is referred to as the “peeling mode.”
The foregoing label printer can also operate in a “non-peeling mode” in which a specified number of labels are printed continuously without an accompanying label peeling operation. In this mode the labels are output without being peeled from the liner.
Because the labels are dispensed in the non-peeling mode without peeling the labels from the web, the paper transportation path downstream from the printing unit in the non-peeling mode is different from the peeling mode. When loading label paper the operator must therefore choose which paper transportation path to use downstream from the printing unit according to which label dispensing mode will be used.
A paper feed operation used when printing and dispensing labels in the peeling mode is also different in the non-peeling mode. More specifically, the label paper is conveyed continuously in the non-peeling mode and is conveyed intermittently in the peeling mode. Changing the dispensing mode is thus not limited to simply changing the paper transportation path, and also requires changing paper feed control and printing control.
Whether the label paper is installed in the paper transportation path for the non-peeling mode or the peeling mode cannot, however, be recognized by a printer according to the prior art. As a result, a subcommand for identifying the dispensing mode of the label dispensing command is added to the printer commands sent from the host computer to the printer and sent to the printer to change the label-dispensing mode.
This method makes changing the label-dispensing mode difficult, however, when the label-dispensing mode must be changed on site where the labels are printed. Addressing the problem of the label paper being loaded to different paper transportation paths in the non-peeling mode and peeling mode, Japanese Unexamined Patent Appl. Pub. H08-295323 (corresponding to U.S. Pat. No. 5,980,138) teaches disposing a web sensor in the transportation path that is used in the peeling mode so that the label printer can detect when the label paper is loaded for the peeling mode, and thus automatically select the label dispensing mode for printing and label dispensing.
The foregoing label printer also has a printer cover that opens and closes the printer housing to enable replacing the label paper and removing paper jams in the paper transportation path. The printer cover can thus be opened to open the label paper compartment so that the label paper can be replaced. The printer cover can also be opened to open the paper transportation path so that paper jams can be removed.
The front cover (printer cover) is positioned on the front of the printer housing in the printer taught in Japanese Unexamined Patent Appl. Pub. H08-295323 (corresponding to U.S. Pat. No. 5,980,138) so that the hopper (label paper compartment) for holding a roll of label paper and the peeling unit (label peeling mechanism) can be opened and closed freely.
The trouble with this printer cover is that the printer cover must be opened completely even to simply change the paper transportation path, and thus the label-dispensing mode, without changing the label paper. This is particularly a problem when the cover is large because a large space is required to open and close the cover.
Furthermore, the host computer must be informed of a mode change when the label paper transportation path is changed to change the label-dispensing mode. The apparatus taught in Japanese Unexamined Patent Appl. Pub. H08-295323 (corresponding to U.S. Pat. No. 5,980,138), however, positions the label sensor in the peeling mode transportation path to detect the label-dispensing mode and automatically print accordingly. The labels are thus printed in the wrong mode if the operator loads the label paper in the wrong transportation path, and the resulting labels are thus typically wasted. For example, if the labels are normally dispensed in the peeling mode and applied to products one at a time, but the label paper is mistakenly loaded in the transportation path for the non-peeling mode, the labels will be continuously printed and dispensed intact on the web. This could result in an entire roll of labels being wasted if a large number of labels is dispensed.